cxl/acpi: Set ACPI's CXL _OSC to indicate RCD mode support
authorTerry Bowman <terry.bowman@amd.com>
Thu, 1 Dec 2022 21:34:27 +0000 (13:34 -0800)
committerDan Williams <dan.j.williams@intel.com>
Mon, 5 Dec 2022 18:32:26 +0000 (10:32 -0800)
ACPI uses the CXL _OSC support method to communicate the available CXL
functionality to FW. The CXL _OSC support method includes a field to
indicate the OS is capable of RCD mode. FW can potentially change it's
operation depending on the _OSC support method reported by the OS.

The ACPI driver currently only sets the ACPI _OSC support method to
indicate CXL VH mode. Change the capability reported to also include
CXL RCD mode.

[1] CXL3.0 Table 9-26 'Interpretation of CXL _OSC Support Field'

Signed-off-by: Terry Bowman <terry.bowman@amd.com>
[rrichter@amd.com: Reworded patch description.]
Signed-off-by: Robert Richter <rrichter@amd.com>
Link: http://lore.kernel.org/r/Y4cRV/Sj0epVW7bE@rric.localdomain
Link: https://lore.kernel.org/r/166993046717.1882361.10587956243041624761.stgit@dwillia2-xfh.jf.intel.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
drivers/acpi/pci_root.c

index 4e3db20..b3c202d 100644 (file)
@@ -493,6 +493,7 @@ static u32 calculate_cxl_support(void)
        u32 support;
 
        support = OSC_CXL_2_0_PORT_DEV_REG_ACCESS_SUPPORT;
+       support |= OSC_CXL_1_1_PORT_REG_ACCESS_SUPPORT;
        if (pci_aer_available())
                support |= OSC_CXL_PROTOCOL_ERR_REPORTING_SUPPORT;
        if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))